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remquo, remquof, remquol - remainder functions

#include <math.h>

double remquo(doublex, doubley, int *quo);

float remquof(floatx, floaty, int *quo);

long double remquol(long doublex, long doubley, int *quo);

The

remquo(),remquof(), andremquol() functions shall compute the same remainder as theremainder(),remainderf(), andremainderl() functions, respectively. In the object pointed to byquo, they store a value whose sign is the sign ofx/yand whose magnitude is congruent modulo 2**nto the magnitude of the integral quotient ofx/y, wherenis an implementation-defined integer greater than or equal to 3.An application wishing to check for error situations should set

errnoto zero and callfeclearexcept(FE_ALL_EXCEPT) before calling these functions. On return, iferrnois non-zero orfetestexcept(FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) is non-zero, an error has occurred.

These functions shall return

xREMy.If

xoryis NaN, a NaN shall be returned.If

xis ±Inf oryis zero and the other argument is non-NaN, a domain error shall occur, and either a NaN (if supported), or an implementation-defined value shall be returned.

These functions shall fail if:

If the integer expression (math_errhandling & MATH_ERRNO) is non-zero, then

Domain Error The xargument is ±Inf, or theyargument is ±0 and the other argument is non-NaN.errnoshall be set to [EDOM]. If the integer expression (math_errhandling & MATH_ERREXCEPT) is non-zero, then the invalid floating-point exception shall be raised.

The following sections are informative.

None.

On error, the expressions (math_errhandling & MATH_ERRNO) and (math_errhandling & MATH_ERREXCEPT) are independent of each other, but at least one of them must be non-zero.

These functions are intended for implementing argument reductions which can exploit a few low-order bits of the quotient. Note that

xmay be so large in magnitude relative toythat an exact representation of the quotient is not practical.

None.

feclearexcept() ,fetestexcept() ,remainder() , the Base Definitions volume of IEEE Std 1003.1-2001, Section 4.18, Treatment of Error Conditions for Mathematical Functions,<math.h>

Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group |
REMQUO (P) | 2003 |